Process for producing liquid pig iron or intermediate steel products and installation for implementing it

ABSTRACT

In a process for producing molten pig iron or steel preproducts from fine-particulate iron containing material in a meltdown gasifying zone of a melter gasifier, under the supply of carbon-containing material and oxygen-containing gas at the simultaneous formation of a reducing gas in a bed formed of solid carbon carriers, the iron-containing material is melted when passing the bed. In order to be able to work with a charge consisting of fine ore by up to 100%, yet reliably avoid discharging of the fine ore supplied, a supply duct for fine-particulate coal, such as coal dust and/or other carbon-containing materials including volatile portions, and a duct feeding an oxygen-containing gas enter in the vicinity of the reducing-gas discharge duct of the melter gasifier, the fine-particulate coal and/or other carbon-containing materials including volatile portions are reacted to fine-particulate coke upon introduction into the melter gasifier, the fine-particulate coke is discharged along with the reducing gas carried off the melter gasifier and is separated in a separating means.

The invention relates to a process for producing molten pig iron orsteel preproducts from fine-particulate iron-containing material, inparticular reduced sponge iron, in a meltdown gasifying zone of a meltergasifier, in which, under the supply of carbon-containing material andoxygen-containing gas at the simultaneous formation of a reducing gas ina bed formed of solid carbon carriers, the iron-containing material ismelted when passing the bed, optionally upon previous completereduction, as well as a plant for carrying out the process. From EP-B -0010 627 a process for producing molten pig iron or steel preproductsfrom particulate iron-containing material, in particular prereducedsponge iron, as well as for producing reducing gas in a melter gasifieris known, in which a fluidized bed is formed of coke particles by addingcoal and by blowing in an oxygen-containing gas. The oxygen-containinggas, or pure oxygen, is injected in the lower region of the meltergasifier. The particulate iron-containing material, in particularprereduced sponge iron, and the lumpy coal are top-charged throughcharging openings provided in the hood of the melter gasifier, thefalling particles are braked in the fluidized bed and theiron-containing particles are reduced and melted while falling throughthe coke fluidized bed. The melted metal covered by slag collects on thebottom of the melter gasifier. Metal and slag are drawn off throughseparate tap openings.

However, a process of this type is not suitable for processingfine-particle sponge iron and fine-particulate coal, since fine-particlesolids particles would be immediately discharged from the meltergasifier due to the violent gas flow prevailing there. Discharging iseven more favored by the temperature prevailing in the upper region ofthe melter gasifier, since this is too low to ensure melting of thesponge iron on the site of charging.

From U.S. Pat. No. 5,082,251 it is known to directly reduceiron-containing fine ore by fluidization by aid of a reducing gasproduced from natural gas. The iron-rich fine ore is reduced by aid of areducing gas under elevated pressure in a system comprised of fluidizedbed reactors arranged in series. After this, the thus produced spongeiron powder is subjected to hot or cold briquetting. Separate meltingaggregates are to be provided for further processing the sponge ironpowder. The treatment of fine-particulate coal is not possible there.

From EP-B -0 111 176 is it known to produce sponge iron particles andmolten pig iron from lumpy iron ore, the iron ore being directly reducedin a direct-reduction aggregate and sponge iron particles dischargedfrom the direct-reduction aggregate being separated into a coarse-grainfraction and a fine-grain fraction. The fine grain fraction is suppliedto a melter gasifier, in which the heat required for melting the spongeiron as well as the reducing gas fed to the direct-reduction aggregateare produced from the coal charged and from the oxygen-containing gasfed. In doing so, coal charging is possible, yet in lumpy form only;fine-particulate coal would be carried off the melter gasifier alongwith the reducing gas.

In a process according to EP-A-0 576 414 lumpy iron ore-containingcharging substances are directly reduced in a reduction shaft furnace bymeans of the reducing gas formed in the meltdown gasifying zone. Thesponge iron thus obtained is then supplied to the meltdown gasifyingzone. In order to be able to additionally utilize, in that known method,fine ore and/or ore dust, such as oxidic iron fine dust incurring in ametallurgical plant, the fine ore and/or the ore dust together with cokedust is supplied to a dust burner operating into the meltdown gasifyingzone and is reacted in a sub-stoichiometric combustion reaction. Such aprocess allows for the efficient working up of fine ore and/or ore dustincurring in a metallurgical plant up to an amount of between 20 and 30%of the overall charge and, thus, the combined processing of lumpy oreand fine ore and also the processing of coke dust. The use of coal dustwould, however, be problematic, because degasification and tar formationand hence caking within the conveying tube would be caused by the hotreduced ore.

The invention aims at avoiding these drawbacks and difficulties and hasas its object to provide a process of the initially defined kind as wellas a plant for carrying out the process, which enable the processing offine-particulate coal and fine-particulate iron-containing material. Onthe one hand, discharging of the fine particles supplied, by thereducing gas produced in the melter gasifier is to be reliably preventedand, on the other hand, possibly required complete reduction of theiron-containing material is to be ensured. In particular, the inventionhas as its object to provide a process by which a charge comprised offine-particulate iron-containing material by 100% can be processed topig iron and/or steel prematerial when charging fine-particulate coal byusing a melter gasifier.

In accordance with the invention, this object with a process of theinitially defined kind is achieved in that a supply duct forfine-particulate coal, such as coal dust and/or other carbon-containingmaterials including volatile portions, and a duct feeding anoxygen-containing gas enter in the vicinity of the reducing-gasdischarge duct of the melter gasifier, the fine-particulate coal and/orother carbon-containing materials including volatile portions arereacted to fine-particulate coke upon introduction into the meltergasifier, the fine-particulate coke is discharged along with thereducing gas carried off the melter gasifier and is separated in aseparating means. According to the invention, the fine-particulate coalis converted into coke in a simple manner, utilizing the dischargingeffect caused by the violent reducing gas flow. This fine-particle cokeis substantially more readily handleable for further use, sincedegasification and tar formation need not be feared any longer. Othercarbon-containing materials including a portion of volatile matter may,for instance, comprise synthetic shredder or fine-particle petroleumcoke.

Preferably, the fine-particulate coke is supplied to the melter gasifieralong with the fine-particulate iron-containing material optionallypreheated and/or reduced by aid of the reducing gas, wherein, accordingto a preferred embodiment, in a killing zone formed above the bed ahigh-temperature combustion and/or gasification zone is formed underdirect oxygen feeding by burning and/or gasifying the fine-particulatecoke supplied to the melter gasifier, into which high-temperaturecombustion and/or gasification zone the fine-particulate iron-containingmaterial is directly introduced, wherein at least surface melting of theiron-containing material and agglomerating of the same are effected bythe heat released during the reaction of the fine-particulate coke.

The thus formed agglomerates have a higher rate of vertical descent onaccount of their increased mass. Thereby and by their enhanced formfactor, i.e., by their more favorable C_(w) value due to extensivesphere formation, the iron-containing material is prevented from beingdischarged by the reducing gas carried off the melter gasifier.

From EP-A-0 217 331 it is known to directly prereduce fine ore byfluidization and to conduct the prereduced fine ore into a meltergasifier and completely reduce and melt the same by means of a plasmaburner under the supply of a carbon-containing reductant. A fluidizedbed and above the same a fluidized bed of coke form within the meltergasifier. The prereduced fine ore or sponge iron powder, respectively,is supplied to a plasma burner provided in the lower section of themelter gasifier. There, it is disadvantageous that, due to the supply ofprereduced fine ore directly in the lower melting region, i.e., in theregion where the melt collects, complete reduction is no longerguaranteed and the chemical composition required for the furtherprocessing of the pig iron cannot be reached in any event. In addition,the introduction of large amounts of prereduced fine ore is not possiblebecause of the fluidized bed and fixed bed, respectively, forming ofcoal in the lower region of the melter gasifier, since it is notpossible to discharge the melting products from the high-temperaturezone of the plasma burner to a sufficient extent. The introduction ofelevated amounts of prereduced fine ore would immediately result inthermal and mechanical failures of the plasma burner.

In order to obtain mixing and working up of the supplied solids in amanner as uniform and complete as possible, the high-temperaturecombustion and/or gasification zone according to the inventionadvantageously is formed centrally and on the upper end of the meltergasifier and the supply of the materials is directed downwards,agglomeration suitably being accelerated and intensified by swirling theiron-containing material in the high-temperature combustion and/orgasification zone and, moreover, oxygen feeding into thehigh-temperature combustion and/or gasification zone likewiseadvantageously being effected under swirling.

According to a preferred variant of operation, the iron-containingmaterial is introduced into the high-temperature combustion and/orgasification zone in a state mixed with the fine-particulate coke.

In addition, it is advantageous if the speed of entry of theiron-containing material into the high-temperature combustion and/orgasification zone is increased by aid of a propellant, such as nitrogenor in-process gas.

According to a preferred embodiment, reducing gas formed in the meltdowngasifying zone is fed to a preheating zone and/or a direct-reductionzone for pretreating the iron-containing material, the preheated and/orreduced iron-containing material being supplied to the high-temperaturecombustion and/or gasification zone in the hot state. Advantageously,fine-particulate coke may additionally be supplied to the preheatingand/or direct reduction zone.

Advantageously, lumpy coal is additionally introduced into the meltdowngasifying zone for the formation of the bed comprised of solid carboncarriers.

A preferred variant is characterized in that the iron-containingmaterial in the preheating and/or direct reduction zone is separatedinto a fine-grain fraction and a coarse-grain fraction, the latterpreferably comprising particles of between 0.5 and 8 mm, and only thefine-grain fraction is introduced into the high-temperature combustionand/or gasification zone and the coarse-grain fraction is introduceddirectly into the melter gasifier, preferably into its killing space.The coarser portions of the reduced iron ore can be charged by gravityalone, if admixed into the high-temperature combustion and/orgasification zone they merely would consume heat. This heat, as aresult, is available to the fine particles for agglomeration. Thus, theburner that serves for the formation of the high-temperature combustionand/or gasification zone can operate more efficiently and optionally maybe dimensioned smaller without affecting agglomeration.

A further preferred variant is characterized in that the reducing gas isfed to the preheating zone and/or direct reduction zone in anon-purified state. Thereby, carbon-containing dust can be separatedfrom the melter gasifier in the preheating and/or direct reduction zone.

A plant for carrying out the process comprising a melter gasifierincluding supply and discharge ducts for the addition ofcarbon-containing material, iron-containing material, for drawing offthe reducing gas produced and for feeding an oxygen-containing gas aswell as, furthermore, a slag and melt tap, a lower section of the meltergasifier being provided for collecting the molten pig iron and/or steelprematerial and the liquid slag, a central section located thereabovebeing provided for accommodating a bed of solid carbon carriers, andfinally an upper section being provided as a killing space, ischaracterized in that the melter gasifier in the vicinity of the openingof the reducing-gas discharge duct comprises a burner for supplyingfine-particulate coal, and that a separating means for separatingfine-particulate coke discharged along with the reducing gas is providedin the reducing-gas discharge duct, a return duct for fine-particulatecoke suitably running from the separating means into the meltergasifier.

Preferably, a burner supplying an oxygen-containing gas andfine-particulate iron-containing material and a supply means forsupplying fine-particulate coke are provided on the upper end of thekilling space.

Preferably, a single burner arranged centrally, i.e., on the verticallongitudinal central axis of the melter gasifier is provided, whoseburner mouth is oriented towards the surface of the bed.

Suitably, the supply of fine-particulate coke likewise is effected viathe burner, the latter advantageously being configured as anoxygen-carbon burner.

In order to obtain thorough mixing of the solids supplied to the burnerboth with one another and with the oxygen-containing gas fed, the burneradvantageously is provided with a swirling means for the solids suppliedvia the burner as well as suitably with an additional swirling means forthe oxygen-containing gas fed via the burner.

A simple burner configuration is feasible if a mixed-material duct forsupplying the fine-particulate iron-containing material and thefine-particulate coke runs into the burner.

According to a further preferred embodiment, a reducing-gas dischargeduct runs into a means for preheating and/or directly reducing thefine-particulate iron-containing material, departing from the killingspace of the melter gasifier.

Preferably, the means for preheating and/or direct reduction comprises afractionating means for separating the iron-containing material into acoarse-grain fraction and a fine-grain fraction and the fine-grainfraction is conducted to the burner via a duct, whereas the coarse-grainfraction is directly supplied to the melter gasifier via a duct.

Suitably, the reducing-gas discharge duct runs directly into the meansfor preheating and/or direct reduction, i.e., without intermediatearrangement of a dust separating means.

BRIEF DESCRIPTION OF THE DRAWINGS

In the appended drawings, FIGS. 1 and 2 each diagrammaticallyillustrates an embodiment of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

By 1 a melter gasifier is denoted, in which a CO and H₂-containingreducing gas is produced from coal and an oxygen-containing gas. Thisreducing gas is conducted off the melter gasifier 1 via a reducing-gasdischarge duct 2 running into a gas purification cyclone 3 and from thecyclone 3 is fed to a reactor 4 for preheating and/or reducingfine-particle iron-containing material 5, such as, e.g., iron-containingdusts, in particular ore dusts, sponge iron dusts, etc. A portion of thereducing gas conducted away through the reducing-gas discharge duct 2,by means of a return duct 6 via a scrubber 7 and a compressor 8, isagain recirculated into the reducing-gas discharge duct 2 in order tocool the reducing gas to the temperature required for its use within thereactor 4. Reactor 4 is provided with a gas discharge outlet 30. Reactor4 is provided with a gas discharge outlet 30.

The reactor 4 advantageously is designed as a shaft furnace. The shaftfurnace also could be replaced with a drum-type furnace or a rotatingfurnace. Furthermore, several fluidized-bed reactors consecutivelyarranged in series could be provided instead of the single reactor 4,the fine ore being conducted from one fluidized bed reactor to anotherthrough conveying ducts in a manner similar to that described in U.S.Pat. No. 5,082,251.

The fine particles separated in the cyclone 3, which are substantiallycomprised of coke particles or coke dust—as will be explained later on,via collecting containers 9 are supplied by means of a return duct 9′ toa burner 11 centrally arranged on the upper end, i.e., top 10 or hood,of the melter gasifier 1, by means of which burner the fine-particulateiron-containing material 5 supplied from the reactor 4 through duct 12is introduced into the melter gasifier 1. Prior to being introduced intothe melter gasifier 1, the coke dust is mixed with the fine-particulateiron-containing material 5 and supplied to the burner 11 through amixed-material duct 13, a propellant duct 14 running into themixed-material duct 13 via an injector 15 to increase the entry speed ofthe solids supplied to the burner 11. Nitrogen, for instance, is used asa propellant. Furthermore, a duct 16 feeding an oxygen-containing gasruns into the burner 11.

The burner mouth 11′ may be designed, for instance, as described in EP-A-0 481 955 with the mixed-material duct 13 running into a centralinternal tube of the burner 11, which is surrounded by an annular gapfeeding said oxygen-containing gas. In principle, the coke might also beconveyed to the burner mouth 11′ via separate lances. Advantageously,the solids supplied to the burner 11 are twisted by means of the burner11 by twisting means (e.g., helically designed outlet channels) whenleaving the burner 11. In addition, twisting of the oxygen jet fed viaan annular space may be effected, thus ensuring particularly goodmixing.

The fine-particulate coke or coke dust discharged from the meltergasifier 1 along with the reducing gas is formed in the followingmanner:

A burner 18 for supplying fine-particulate coal 19 and/or othercarbon-containing materials having volatile portions opens in thevicinity of i.e., near the opening 17, or of several openings 17, of thereducing-gas discharge duct 2 of the melter gasifier 1. These maycomprise, for instance, synthetic shredder waste or fine-particlepetroleum coke. They are supplied to the burner 18 by aid of apropellant, such as nitrogen, which is fed via an injector 20.Furthermore, a duct 21 feeding an oxygen-containing gas runs into theburner 18.

A reaction—a partial combustion—of the supplied fine coal 19 tofine-particulate coke or coke dust 19′ takes place, the latter beingdischarged almost completely along with the reducing gas due to theburner 18 being arranged in the vicinity of the opening 17 of thereducing-gas discharge duct 2, and separated in the cyclone 3.

On its upper end 10, the melter gasifier 1 comprises a supply duct 22for lumpy carbon carriers, such as coal, as well supply ducts 23arranged farther below for oxygen-containing gases as well as optionallysupply ducts for carbon carriers liquid or gaseous at room temperature,such as hydrocarbons, as well as for burnt fluxes.

Molten pig iron 24 and/or molten steel prematerial and molten slag 25collect in the melter gasifier 1 in a lower section I and are tapped viaa tap 26.

In a section II arranged above the lower section I, of the meltergasifier 1, a fixed bed and/or a fluidized bed 27 forms of the solidcarbon carriers charged. The supply ducts 23 for oxygen-containing gasesopen into this section II. An upper section III provided above thecentral section II functions as a killing space for the reducing gasforming in the melter gasifier 1 as well as for solids particlesentrained with the gas flow. In the upper section III, there is theopening 17 of the reducing-gas discharge duct 2 and enters the burner 18supplying the fine-particulate coal 19.

A high-temperature combustion and/or gasification zone 28 is formed atthe burner mouth 11′ of the burner 11, in which the fine particles ofthe iron-containing material 5 are melted completely or at leastsurfacially under the formation of droplets, thus causing theiron-containing fine-particles to agglomerate. Thereby, thefine-particulate iron-containing material 5 is effectively preventedfrom being discharged along with the reducing gas conducted away fromthe melter gasifier 1.

The droplet agglomerates forming have greater hydraulic diameters and/orhigher densities and hence higher descending speeds than the fineparticles. This descending speed is even further improved by theenhanced form factor, i.e. C_(w) value, of the droplet agglomeratesforming.

The arrangement of the burner 11 in a central region on top 10 of themelter gasifier 1 allows for uniform mixing of the solids particlessupplied and hence complete agglomeration. As a result, the ironcarriers are uniformly integrated in the fixed and/or fluidized bed 27formed in the melter gasifier of solid carbon carriers. Thus, it isfeasible to realize the melt-reduction process with 100% fine ore and toavoid discharging of the iron carriers from the melter gasifier 1 in thesolid state.

The grain size of the fine-particulate coal intended to be used with theprocess according to the invention preferably ranges between 1 and 0 cmand that of the fine-particulate iron-containing material between 8 and0 cm.

The dust recycling via cyclone 3 illustrated might be clearly reducedand optionally even omitted as shown in FIG. 2, since dust supplied tothe reactor 4 via duct 2′ indicated in broken lines (duct 2 betweencyclone 3 and reactor 4 may be omitted in that case) is again dischargedfrom the reactor 4 and supplied to the burner 11 along with thepreheated and optionally prereduced solids and may be thermally utilizedin the high-temperature zone 28. In that case, the cyclone 3 may, thus,be omitted or devised only with a view to the recirculating amount ofreducing gas.

Preferably, the reactor 4 might be equipped with a fractionating means,the coarse-grain fraction (particles of between 0.5 and 8 mm) beingsupplied to the melter gasifier 1 directly, e.g., by means of gravitycharging through duct 12′, and the fine particles being supplied to thehigh-temperature combustion and/or gasification zone 28 through duct 12.

This causes the burner 11 to be relieved such that its heat is availableexclusively for the finest particles, which have to be agglomerated inany event in order to avoid discharging of the same. The grain sizes ofthe particles of the coarse-grain fraction should be so such that thedescending speed of those particles is slightly higher than thesuperficial velocity in the zone III of the melter gasifier 1. Thereby,discharging of those particles is prevented.

EXAMPLE

1,020 kg coal/ton PI (pig iron), thence 340 kg fine coal/ton PI 19 andthe balance in the form of lumpy coal (at 22) as well as 1,460 kgfine-particulate iron-containing material 5/ton PI are charged toproduce 40 tons of pig iron/hour by means of a plant according to thedrawing.

Coal:

Chemical analysis of coal (fine coal 19 and lumpy coal, weight portions,dry basis)

C 77.2%  H 4.6% N 1.8% O 6.8% S 0.5% ashes 9.0% C-fix 63.0% 

Grain size distribution of fine coal 19

−500 μm 100%  −250 μm 85% −100 μm 51%  −63 μm 66%  −25 μm 21%

Fine-particulate iron-containing material:

Chemical analysis (weight portions):

Fe_(tot) 66.3%  Fe₀ 0.4% Fe₂O₃ 94.5%  Loss on ignition 1.0% Moisture1.0%

Grain size distribution

−4000 μm 100%  −1000 μm 97%  −500 μm 89%  −250 μm 66%  −125 μm 25%

Fluxes:

Chemical analysis (weight portions):

CaO 34.2%  MgO 9.9% SiO₂ 14.1%  Al₂O₃ 0.3% Fe₂O₃ 1.1% MnO 0.5% Loss onignition 39.1% 

321 Nm³ O₂/ton PI are introduced into bed 27 through supply ducts 23designed as tuyeres to gasify the coal, the consumption of the burner 11being 255 Nm³O₂/ton PI and of the burner 18 being 75 Nm³O₂/ton PI.

Pig iron 24:

Chemical analysis (weight portions):

C  4.3% Si  0.4% Mn 0.09% P  0.1% S 0.05% Fe 95.0%

Export gas:

Amount: 1,720 Nm³/ton PI

Analysis (volume portions):

CO 38.7% CO₂ 37.2% H₂ 16.4% H₂O 2% N₂ + Ar 4.6% CH₄ 1.1%

Heating value: 7,060 kj/Nm³

What is claimed is:
 1. A process for producing pig iron or steelproducts from fine-particulate iron-containing material in a meltdowngasifying zone of a meltdown-gasifier, comprising introducing carboncontaining material into said zone via a burner provided at the top ofthe meltdown-gasifier, and introducing fine-particulate iron-containingmaterial into said zone, and introducing an oxygen-containing gas intosaid zone, and thereby producing molten pig iron and/or steelprematerial, slag, fine particulate coke, and a reducing gas in areaction bed formed in said zone, and withdrawing said reducing gas andsaid fine-particulate coke from an outlet on the upper section of saidmeltdown gasifier, and introducing additional carbon-containing materialin the form of fine particulate coal and/or other carbon-containingmaterial having volatile portions near said outlet for withdrawing saidreducing gas, and at least a portion of said oxygen-containing gas beingintroduced near said outlet for withdrawing said reducing gas, andseparately drawing off said slag and said molten pig iron and/or steelprematerial in a lower section of said meltdown gasifier.
 2. A processaccording to claim 1, characterized in that the fine-particulate coke issupplied to the melter gasifier along with the fine-particulateiron-containing material.
 3. A process according to claim 2,characterized in that in a killing zone formed above the reaction bed ahigh-temperature combustion and/or gasification zone is formed byburning and/or gasifying under direct oxygen feeding thefine-particulate coke supplied to the melter gasifier, into whichhigh-temperature combustion and/or gasification zone thefine-particulate iron-containing material is directly introduced,wherein at least surface melting of the iron-containing material andagglomerating of the same are effected by the heat released during thereaction of the fine-particulate coke.
 4. A process according to claim3, characterized in that the high-temperature combustion and/orgasification zone is formed centrally and on the upper end of the meltergasifier and the supply of the materials is effected in a downwardlyoriented manner.
 5. A process according to claim 3, characterized inthat agglomeration is accelerated and intensified by swirling theiron-containing material in the high-temperature combustion and/orgasification zone.
 6. A process according to claim 5, characterized inthat oxygen feeding into the high-temperature combustion and/orgasification zone likewise is effected under swirling.
 7. A processaccording to claim 3, characterized in that the iron-containing materialis introduced into the high-temperature combustion and/or gasificationzone in a state mixed with the fine-particulate coke.
 8. A processaccording to claim 3, characterized in that the speed of entry of theiron-containing material and of the fine-particulate coke into thehigh-temperature combustion and/or gasification zone is increased by aidof a propellant.
 9. A process according to claim 3, characterized inthat reducing gas formed in the meltdown gasifying zone is fed to apreheating zone and/or a direct-reduction zone for pretreating theiron-containing material, the preheated and/or prereducediron-containing material being supplied to the high-temperaturecombustion and/or gasification zone in the hot state.
 10. A processaccording to claim 9, characterized in that fine-particulate coke isadditionally supplied to the preheating and direct reduction zone.
 11. Aprocess according to claim 1, characterized in that lumpy coal isadditionally introduced into the meltdown gasifying zone.
 12. A processaccording to claim 9, characterized in that the iron-containing materialin the preheating and/or direct reduction zone is separated into afine-grain fraction and a coarse-grain fraction, the latter preferablycomprising particles of between 0.5 and 8 mm, and only the fine-grainfraction is introduced into the high-temperature combustion and/orgasification zone and the coarse-grain fraction is introduced directlyinto the melter gasifier.
 13. A process according to claim 9,characterized in that the reducing gas is fed to the preheating zoneand/or direct reduction zone in a non-purified state.
 14. A plant forcarrying out the process according to claim 1, comprising a meltergasifier including supply and discharge ducts for the addition ofcarbon-containing material, iron-containing material, for drawing offthe reducing gas produced and for feeding oxygen-containing gas and aslag and melt tap, a lower section of the melter gasifier being providedfor collecting the molten pig iron and/or steel prematerial and theliquid slag, a central section located above the lower section beingprovided for accommodating a bed of solid carbon carriers, and an uppersection being provided as a killing space.
 15. A plant according toclaim 14, characterized in that a return duct for fine-particulate coke(19′) runs from the separating means (3) into the melter gasifier (1).16. A plant according to claim 15, characterized in that at least oneburner (11) supplying an oxygen-containing gas and fine-particulateiron-containing material (5) and a supply means for supplying thefine-particulate coke (19′) are provided on the upper end of the killingspace (III).
 17. A plant according to claim 16, characterized in that asingle burner (11) arranged on the vertical longitudinal central axis ofthe melter gasifier (1) is provided, whose burner mouth (11′) isoriented towards the surface of the bed (27).
 18. A plant according toclaim 16, characterized in that the burner also serves for supplyingfine-particulate coke.
 19. A plant according to claim 16, characterizedin that the burner is provided with a swirling means for the solidssupplied via the burner.
 20. A plant according to claim 16,characterized in that the burner (11) is provided with a swirling meansfor the oxygen-containing gas fed via the burner (11).
 21. A plantaccording to claim 16, characterized in that a mixed-material duct (13)for supplying the fine-particulate iron-containing material (5) and thefine-particulate coke (19′) opens into the burner.
 22. A plant accordingto claim 14, characterized in that a reducing-gas discharge duct (2)runs into a means (4) for preheating and/or directly reducing thefine-particulate iron-containing material (5), departing from thekilling space (III) of the melter gasifier (1).
 23. A plant according toclaim 22, characterized in that the means (4) for preheating and/ordirect reduction comprises a fractionating means for separating theiron-containing material into a coarse-grain fraction and a fine-grainfraction and the fine-grain fraction is conducted to the burner (11) viaa duct (12), whereas the coarse-grain fraction is directly supplied tothe melter gasifier (1) via a duct (12′).
 24. A plant according to claim22, characterized in that the reducing-gas discharge duct (2) runsdirectly into the means (4) for preheating and/or direct reduction,i.e., without intermediate arrangement of a dust separating means (3).25. A merchantable product made of pig iron or steel preproductsproduced by a process according to claim
 1. 26. A process according toclaim 1, wherein the withdrawn fine particulate coke is separated fromthe withdrawn reducing gas.
 27. A process according to claim 1, whereinsaid fine-particulate iron-containing material is sponge iron.
 28. Aprocess according to claim 1, wherein said iron-containing material iscompletely reduced in said reaction bed.
 29. A process according toclaim 8, wherein said propellant is nitrogen or an in-process gas.
 30. Amerchantable product according to claim 25, said product being rolledstock.
 31. A process according to claim 2, wherein said fine-particulateiron-containing material is preheated and/or reduced by aid of thereducing gas.
 32. A process according to claim 12, wherein thecoarse-grain fraction is introduced into the killing space of the meltergasifier.